Association between Toxoplasma gondii exposure and abdominal pain: An age- and gender-matched case-control seroprevalence study

Abdominal pain has been rarely reported in individuals infected with Toxoplasma gondii (T. gondii). The aim of this study was to determine the association between T. gondii infection and abdominal pain. Two hundred and ninety-nine patients with abdominal pain (cases) and 299 age- and gender-matched people without abdominal pain (controls) were tested for anti-T. gondii IgG and IgM antibodies. Twenty-four (8.0%) of the 299 cases and 12 (4.0%) of the 299 controls were positive for anti-T. gondii IgG antibodies (OR: 2.08; 95% CI: 1.02-4.25; P = 0.03). The seroprevalence of T. gondii infection was significantly higher in women with frequent abdominal pain than in women without this clinical feature (OR: 2.30; 95% CI: 1.06-4.96; P = 0.02). Twelve (4.0%) of the 299 cases and 7 (2.3%) of the 299 controls had high (>150 IU mL-1) anti-T. gondii IgG antibody levels (OR: 1.74; 95% CI: 0.67-4.49; P = 0.24). Seven (29.2%) of the 24 cases with anti-T. gondii IgG antibodies and 3 (25.0%) of the 12 controls with anti-T. gondii IgG antibodies were positive to anti-T. gondii IgM antibodies (OR: 1.23; 95% CI: 0.25-5.97; P = 1.00). Results suggest an association between T. gondii infection and frequent abdominal pain. Further research to confirm this association should be conducted.

Association between ABO and Rh blood groups and Toxoplasma gondii infection: A cross sectional study

We aimed to determine the association between the seropositivity to Toxoplasma gondii and the ABO and Rh blood groups in 2,053 people. ABO and Rhesus blood groups and anti-T. gondii IgG and IgM antibodies were determined using commercially available assays. Of the 2,053 people studied, 171 (8.3%) were positive for anti-T. gondii IgG antibodies. Sixty-five (38.0%) and 36 (21.1%) of these 171 individuals had high anti-T. gondii IgG antibody levels (≥150 IU mL-1) and anti-T. gondii IgM antibodies, respectively. We found the following prevalences of T. gondii infection among the ABO groups: 8.5% in group A, 4.3% in group B, 4.7% in group AB, and 8.9% in group O (P = 0.19). The prevalences of T. gondii infection among Rh groups were: 8.4% in the Rh-positive group and 7.1% in the Rh-negative group (P = 0.58). Logistic regression analysis showed that the frequencies of ABO and Rh blood groups were similar (P > 0.05) among people with positive and negative serology for anti-T. gondii IgG antibodies, with high (≥150 IU mL-1) and lower (<150 IU mL-1) levels of anti-T. gondii IgG antibodies, and with positive and negative serology for anti-T. gondii IgM antibodies. Results does not support an association between T. gondii infection and ABO and Rh blood groups.

Seroprevalence of Toxoplasma gondii in Women of Reproductive Age and Associated Risk Factors in Chiapas, Mexico

Background: We analyzed the seroepidemiology of Toxoplasma gondii infection in women of reproductive age in Chiapas, Mexico. Materials and Methods: One hundred seven women (mean age 25.3 years; range: 13-42 years) were enrolled in a public hospital. The presence of immunoglobulin G (IgG) antibodies to T. gondii in serum samples of participants was determined by an enzyme immunoassay. Bivariate and logistic regression analyses were used to determine the association between characteristics of women and seropositivity to T. gondii. Results: Of the 107 women surveyed, 49 (45.8%) were positive for anti-T. gondii IgG antibodies. T. gondii infection was positively associated with cats at home (odds ratio [OR] = 3.85; 95% confidence interval [CI]: 1.21-12.20; p = 0.02), and negatively associated with eating out of home (OR = 0.29; 95% CI: 0.11-0.80; p = 0.01). Conclusions: This is the highest T. gondii exposure rate in women of reproductive age reported in Mexico.

Toxoplasma gondii infection of the central nervous system and suicide: A case-control study of decedents

We sought to determine the association between Toxoplasma gondii (T. gondii) infection of the central nervous system and suicide in a sample of decedents in Mexico City. One hundred and forty-seven decedents (87 who committed suicide and 60 who did not commit suicide) were studied. Brain tissues (amygdala and prefrontal cortex) of decedents were examined for the detection of T. gondii using immunohistochemistry. Detection of T. gondii was positive in 7 (8.0%) of the 87 cases (6 found in prefrontal cortex and one in amygdala), and in one (1.7%) of the 60 controls (found in prefrontal cortex) (OR: 5.16; 95% CI: 0.61-43.10; P = 0.14). Results suggest that T. gondii infection in brain is not associated with suicide. Further studies to confirm this finding are needed.

Toxoplasma gondii Infection and Alcohol Consumption: An Age-and Gender-Matched Case-Control Seroprevalence Study

The Article Abstract is not available.

Survey on the association between Toxoplasma gondii infection and violent behavior in inmates

We evaluated the association between T. gondii seropositivity and violent behavior in a sample of inmates in Durango, Mexico. Through a cross-sectional study design, we studied 128 inmates (mean age: 35.89 ± 10.51; range: 19-65 years). Sera of participants were analyzed for anti-T. gondii IgG antibodies using a commercially available enzyme-linked immunosorbent assay. Violence was assessed by 1) the Historical, Clinical and Risk Management-20 (HCR-20) tool; 2) the type of the crime for which inmates were convicted; and 3) the Buss-Perry Aggression Questionnaire (AGQ). Of the 128 inmates, 17 (13.3%) had high risk of violence by the HCR-20 criteria, 72 (56.3%) were considered violent by the type of the crime committed, and 59 (46.1%) were considered violent by the AGQ. Depending on the evaluation method of violence, the seroprevalence of T. gondii infection in violent inmates varied from 0% to 6.9%. No statistically significant difference in anti-T. gondii IgG seroprevalence between violent and non-violent inmates was found (for instance by AGQ, OR: 1.17; 95% CI: 0.22-6.07; P = 1.00). Mean scores of the AGQ in T. gondii seropositive inmates (73.67 ± 29.09; 95% CI: 50.00-99.31) were similar to those (79.84 ± 25.00; 95% CI: 75.46-84.27) found in T. gondii seronegative inmates (P = 0.55). Mean scores of anger, psychical aggression, verbal aggression, and hostility in T. gondii seropositive inmates were similar to those found in T. gondii seronegative inmates. Results of this study suggest that infection with T. gondii is not associated with violence in inmates in Durango, Mexico. Further studies with larger sample sizes and in several correctional facilities to determine the association between T. gondii infection and violence in inmates are needed.

Toxoplasma gondii infection and insomnia: A case control seroprevalence study

We determined the association between Toxoplasma gondii (T. gondii) infection and insomnia. Through an age-and gender-matched case-control study, 577 people with insomnia (cases) and 577 people without insomnia (controls) were tested for anti-T. gondii IgG and IgM antibodies using commercially available enzyme-immunoassays. Anti-T. gondii IgG antibodies were found in 71 (12.3%) of 577 individuals with insomnia and in 46 (8.0%) of 577 controls (OR = 1.62; 95% CI: 1.09–2.39; P = 0.01). Men with insomnia had a higher (16/73: 21.9%) seroprevalence of T. gondii infection than men without insomnia (5/73: 6.8%) (OR: 3.81; 95% CI: 1.31–11.06; P = 0.009). The rate of high (>150 IU/ml) anti-T. gondii IgG antibody levels in cases was higher than the one in controls (OR = 2.21; 95% CI: 1.13–4.31; P = 0.01). Men with insomnia had a higher (8/73: 11.0%) rate of high anti-T. gondii IgG antibody levels than men without insomnia (0/73: 0.0%) (P = 0.006). The rate of high anti-T. gondii IgG antibody levels in cases >50 years old (11/180: 6.1%) was higher than that (3/180: 1.7%) in controls of the same age group (OR: 3.84; 95% CI: 1.05–14.00; P = 0.05). No difference in the rate of IgM seropositivity between cases and controls was found (OR = 1.33; 95% CI: 0.57–3.11; P = 0.50). Results of this seroepidemiology study suggest that infection with T. gondii is associated with insomnia. Men older than 50 years with T. gondii exposure might be prone to insomnia. Further research to confirm the association between seropositivity and serointensity to T. gondii and insomnia is needed.

Association between Toxoplasma gondii Infection in Brain and a History of Depression in Suicide Decedents: A Cross-Sectional Study

We assessed the association between Toxoplasma gondii (T. gondii) infection of the central nervous system and suicide correlates in suicide decedents. Eighty-seven decedents who died by suicide received in a forensic setting for medico-legal autopsies in Mexico City were studied. Two samples of brain (amygdala and prefrontal cortex) from each decedent were examined for detection of T. gondii using immunohistochemistry. Correlates of suicide including a history of previous suicide attempts, co-morbid mental disorder, consumption of alcohol or tobacco, irritability and aggression, economic problems, presence of drugs or alcohol in blood and suicide method were obtained and analyzed for their association with T. gondii infection. T. gondii immunohistochemistry was positive in prefrontal cortex sections in 6 decedents and in an amygdala section in one decedent. Thus, the prevalence of T. gondii infection in brain in suicide victims was 8.0% (7/87). Bivariate and logistic regression analysis of suicide correlates showed that only a history of depression was associated with T. gondii infection of the brain in suicide victims (OR: 12.00; 95% CI: 2.26–63.46; p = 0.003). Our results provide evidence that T. gondii infection in brain is associated with a history of depression in suicide decedents.

Hepatitis E virus infection and waste pickers: A case-control seroprevalence study

Whether waste pickers are a risk group for hepatitis E virus (HEV) infection is largely unknown. This study aimed to determine the association between HEV exposure and the occupation of waste pickers and the work characteristics of waste pickers. An age-and gender-matched case-control seroprevalence study of 86 waste pickers and 86 control subjects of the general population was performed. We determined anti-HEV IgG antibodies in sera of cases and controls using a commercially available enzyme-linked immunoassay. The McNemar's test was used to assess the association between HEV seropositivity and the occupation of waste picker. The association between HEV seropositivity and work characteristics of waste pickers was assessed by bivariate and logistic regression analyses. Anti-HEV IgG antibodies were detected in 14 (16.3%) of the 86 waste pickers and in 8 (9.3%) of the 86 control subjects (McNemar's pair test: odds ratio (OR) = 13.0; 95% confidence interval (CI): 0.73-230.77; p = .02). Bivariate analysis showed that HEV exposure was associated with an ill status (p = .01) and reflexes impairment (p = .009). Logistic regression analysis showed that HEV seropositivity was associated with increasing age (OR = 6.52; 95% CI: 1.95-21.78; p = .002) and raising pigs (OR = 12.01; 95% CI: 1.48-97.26; p = .02). This is the first age- and gender-matched case-control study on the association between HEV infection and the occupation of waste picker. Waste pickers represent a risk group for HEV infection. Factors associated with HEV seropositivity found in this study may help in the design of optimal planning to avoid HEV infection.

Association between Toxoplasma gondii Exposure and Suicidal Behavior in Patients Attending Primary Health Care Clinics

This study aimed to determine the association between suicidal behavior and T. gondii seroreactivity in 2045 patients attending primary care clinics. IgG antibodies against T. gondii were found in 37 (12.1%) out of 306 individuals with a history of suicidal ideation and in 134 (7.7%) of 1739 individuals without this history (OR: 1.64; 95% CI: 1.11–2.42; p = 0.01). Seropositivity to T. gondii was associated with suicidal ideation in women (OR: 1.56; 95% CI: 1.01–2.42; p = 0.03) and individuals aged ≤30 years (OR: 3.25; 95% CI: 1.53–6.88; p = 0.001). No association between the rates of high (>150 IU/mL) levels of anti-T. gondii IgG antibodies and suicidal ideation or suicide attempts was found. IgG antibodies against T. gondii were found in 22 of 185 (11.9%) individuals with a history of suicide attempts and in 149 (8.0%) of 1860 individuals without this history (OR: 1.54; 95% CI: 0.96–2.49; p = 0.06). The seroprevalence of T. gondii infection was associated with suicide attempts in individuals aged 31–50 years (OR: 2.01; 95% CI: 1.09–3.71; p = 0.02), and with more than three suicide attempts (OR: 4.02; 95% CI: 1.34–12.03; p = 0.008). Our results indicate that T. gondii exposure is associated with suicidal behavior among patients attending primary care clinics.

Leptospira infection in people in the city of Durango, Mexico: a cross sectional study

Objective

To determine the seroprevalence of Leptospira immunoglobulin (Ig)G and IgM antibodies and its association with the characteristics of the study population from the northern Mexican city of Durango, Mexico.

Methods

Through a cross-sectional study design, inhabitants of Durango City, Mexico were surveyed between June 2018 and November 2018. Serum samples from the subjects were analysed for anti-Leptospira IgG and IgM antibodies using commercially available enzyme-linked immunosorbent assays. Sociodemographic, clinical, behavioural and housing characteristics were recorded. Data were analysed by bivariate and multivariate analyses.

Results

The study enrolled 413 people, of which 124 (30.0%) and 137 (33.2%) were positive for anti-Leptospira IgG antibodies and anti-Leptospira IgM antibodies, respectively. Multivariate analysis showed that Leptospira seropositivity was associated with professional occupation, alcohol consumption, ill clinical status, memory impairment and a history of surgery.

Conclusions

This is the first study to report the seroepidemiology of Leptospira infection in an urban general population in the north of Mexico. The seroprevalence of Leptospira infection found was higher than those previously reported in Mexican studies.

Hepatitis E Virus Infection and Butchers: A Case-Control Seroprevalence Study

Background

Very few case-control studies to assess the risk of hepatitis E virus (HEV) infection in meat workers have been published. Therefore, we sought to determine: 1) the association of HEV IgG seropositivity and the occupation of butcher; and 2) the sociodemographic, work, clinical and behavioral characteristics of butchers associated with HEV exposure.

Methods

We performed a case-control seroprevalence study of 101 butchers (mean age: 38.50 ± 12.52 years) and 101 age-, gender- and residence-matched control subjects of the general population. Anti-HEV IgG antibodies were determined using a commercially available enzyme-linked immunoassay. Bivariate and regression analyses were used to assess the association between HEV seropositivity and characteristics of butchers.

Results

Anti-HEV IgG antibodies were found in 18 (17.8%) of the 101 butchers and in 14 (13.9%) of the 101 control subjects (odds ratio (OR): 1.34; 95% confidence interval (CI): 0.63 - 2.88; P = 0.44). Stratification by sex, age and area of residence (rural or urban) in cases and controls showed similar seroprevalences of HEV infection among groups. Bivariate analysis showed that HEV seroprevalence was associated with low education (up to 6 years), work place, seniority, eating while working, a history of raising farm animals and national trips. However, further analysis by logistic regression showed that only the variable of national trips was associated with HEV exposure (OR: 5.38; 95% CI: 1.02 - 28.16; P = 0.04). Concerning clinical characteristics of butchers, no association between HEV exposure and health status, history of surgery or blood transfusion was found.

Conclusions

Results from this first age-, gender- and residence-matched serosurvey of HEV infection in butchers in Mexico suggest that this population group does not have a higher risk for HEV infection than people from the general population. However, further studies to confirm the lack of association between HEV infection and the occupation of butcher are needed.

Seroprevalence of IgG and IgM anti-Toxoplasma gondii antibodies and associated risks factors in pregnant women of northern Durango, Mexico

Toxoplasmosis is caused by intracellular parasite Toxoplasma gondii (T. gondii). T. gondii infection in pregnancy can result in serious consequences for the developing fetus or newborn, including spontaneous abortion, hydrocephalus, and even death (1).  The infection could be acquired by ingestion of food (raw or uncooked meat from infected animals), direct contact with cat feces or soil contaminated with oocysts.  In 2012 Caballero-Ortega et al., (2) found an increase in the toxoplasmosis distribution in the north region (35%) finding the highest prevalence in coastal regions (67.5%) of México. There is no data historic available about this seroprevalence, specifically of the “Comarca Lagunera” of Durango State. Moreover, previous study of T. gondii seroprevalence in Durango City showed that 6.1% of pregnant woman of urban areas and 8.2% of rural areas were found positives (3). In 2018, 434 pregnant women who used the Health Services of Durango State in the “Comarca Lagunera Region” were studied with an average age of 22.2 years (± 5.95); we found four (0.92%) IgG and none (0.0%) IgM antibodies anti-T. gondii (Table I). Consumption of dried meat (OR = 16.5; 95% CI 1.7 – 161.48; p= 0.01) and sheep and goat meat (OR = 15.61; 95% CI 1.1 – 224.05; p= 0.043) were associated factors to the infection. Number and different types of pets and cats was not associated with anti-T. gondii antibodies. The “Comarca Lagunera” of Durango being a cattle zone, frequently local meat is consumed in general, representing a possible risk factor. It is particularly interesting since this study’s seroprevalence was 0.91% in a small area of Durango State, differing from the global prevalence in the State.  Probably, this results could be due to Durango State having a geographical diversity, Durango capital is located in a valley, unlike the “Comarca Lagunera” region, which is a semi-desert zone with high environmental temperature (Up to 45°C), that could explain the reduced survival of oocysts which implies a subsequent investigation to this work.

Toxoplasma gondii infection in pregnant women: a cross-sectional study in Matehuala City, Mexico

OBJECTIVES

This study aimed to determine the seroprevalence of Toxoplasma gondii (T. gondii) infection in pregnant women in Matehuala City, Mexico; and the associated risk factors.

DESIGN

A cross-sectional study.

SETTING

Matehuala City, Mexico.

PARTICIPANTS

311 pregnant women.

PRIMARY AND SECONDARY OUTCOME MEASURES

Sera of women were analysed for anti-T. gondii IgG and IgM antibodies by commercially available immunoassays. Bivariate and multivariate analyses were used to assess the association between T. gondii seroprevalence and the characteristics of the pregnant women.

RESULTS

Thirteen (4.2%) of the 311 pregnant women studied were positive for anti-T. gondii IgG antibodies. No anti-T. gondii IgM antibodies were found in anti-T. gondii IgG seropositive women. No association between seropositivity and history of blood transfusion, transplantation, caesarean sections, deliveries, miscarriages or number of pregnancies was found. Logistic regression analysis of sociodemographic, behavioural and housing variables showed that availability of potable water at street represented a risk factor for T. gondii infection (age-adjusted OR=2.18; 95% CI: 1.05 to 4.53; p=0.03), whereas being born in Mexico was a protective factor for infection (age-adjusted OR=0.01; 95% CI: 0.001 to 0.35; p=0.008).

CONCLUSIONS

In this first study on the seroepidemiology of T. gondii infection in pregnant women in Matehuala, we conclude that the seroprevalence of T. gondii infection is low and similar to those reported in pregnant women in other Mexican cities. However, the seroprevalence found is lower than those reported in pregnant women in other countries in the Americas and Europe. Two risk factors associated with T. gondii infection were identified. Results of the present study may help for the optimal planning of preventive measures against toxoplasmosis in pregnant women.

Toxoplasma gondii infection and multiple sclerosis: An age- and a gender-matched case-control seroprevalence study

The link between Toxoplasma gondii infection and multiple sclerosis remains controversial. In the present study, we aimed to determine the association between T.gondii seropositivity and multiple sclerosis. Using an age- and gender-matched case-control study, we studied 45 patients who had multiple sclerosis attended in two public hospitals and 225 control subjects without this disease and other neurological disorders in Durango City, Mexico. Serum samples of cases and controls were analyzed for detection of anti-Toxoplasma IgG using a commercially available enzyme-linked immunoassay. One (2.22%) of the 45 patients with multiple sclerosis, and 15 (6.67%) of the 225 control subjects without this disease were seropositive for anti-T. gondii IgG antibodies. No statistically significant difference (OR = 0.31; 95% CI: 0.04–2.47; P = 0.48) in seroprevalence of anti-T. gondii IgG antibodies between cases and controls was found. The frequency of T. gondii seropositivity did not vary among cases and controls about sex or age groups. Results of this study do not support an association between seropositivity to T. gondii and multiple sclerosis. However, additional research with larger sample sizes to confirm this lack of association should be conducted.

Comparison of major depression diagnostic classification probability using the SCID, CIDI, and MINI diagnostic interviews among women in pregnancy or postpartum: An individual participant data meta-analysis

OBJECTIVES

A previous individual participant data meta-analysis (IPDMA) identified differences in major depression classification rates between different diagnostic interviews, controlling for depressive symptoms on the basis of the Patient Health Questionnaire-9. We aimed to determine whether similar results would be seen in a different population, using studies that administered the Edinburgh Postnatal Depression Scale (EPDS) in pregnancy or postpartum.

METHODS

Data accrued for an EPDS diagnostic accuracy IPDMA were analysed. Binomial generalised linear mixed models were fit to compare depression classification odds for the Mini International Neuropsychiatric Interview (MINI), Composite International Diagnostic Interview (CIDI), and Structured Clinical Interview for DSM (SCID), controlling for EPDS scores and participant characteristics.

RESULTS

Among fully structured interviews, the MINI (15 studies, 2,532 participants, 342 major depression cases) classified depression more often than the CIDI (3 studies, 2,948 participants, 194 major depression cases; adjusted odds ratio [aOR] = 3.72, 95% confidence interval [CI] [1.21, 11.43]). Compared with the semistructured SCID (28 studies, 7,403 participants, 1,027 major depression cases), odds with the CIDI (interaction aOR = 0.88, 95% CI [0.85, 0.92]) and MINI (interaction aOR = 0.95, 95% CI [0.92, 0.99]) increased less as EPDS scores increased.

CONCLUSION

Different interviews may not classify major depression equivalently.

Low Toxocara Seroprevalence in People in Rural Durango, Mexico

The epidemiology of Toxocara infection in rural Mexico is largely unknown. Therefore, we sought to determine the seroprevalence of Toxocara infection in rural people in a northern Mexican state. We performed a cross-sectional seroprevalence study of 641 people living in rural Durango State including 282 subjects of the general population, 214 subjects of Huichol ethnicity, and 145 subjects of Mennonite ethnicity. Sera of participants were analyzed for the presence of anti-Toxocara immunoglobulin G (IgG) antibodies using a commercially available enzyme immunoassay. Three (0.5%) of the 641 subjects tested were positive for anti-Toxocara IgG antibodies. Of the 3 Toxocara seropositive subjects, two were females, aged 19 and 39 years, and one was male, aged 59 years. They had contacted with dogs, cleaned cat excrement, consumed unwashed raw fruits, contacted soil, or lived in a house with soil floors. Seroprevalence of Toxocara infection was similar among the 3 groups of population studied: 0.4% for the general population, 0.9% for Huicholes, and 0.0% for Mennonites (P = 0.41). In conclusion, the Toxocara seroprevalence found in subjects in rural Durango is low as compared with those reported in people from rural areas in other countries.

Association between Toxoplasma gondii infection and thyroid dysfunction: a case-control seroprevalence study

Background

The association between Toxoplasma gondii infection and thyroid disease has been poorly studied. Therefore, we sought to determine the association between T. gondii seropositivity and thyroid dysfunction.

Methods

We performed an age- and gender-matched case-control study of 176 patients suffering from hypothyroidism (n = 161) or hyperthyroidism (n = 15) and 528 control subjects without these diseases in a public hospital in Durango City, Mexico. Anti-Toxoplasma IgG antibodies were determined in sera from cases and controls using a commercially available enzyme-linked immunoassay.

Results

Anti-T. gondii IgG antibodies were found in 11 (6.3%) of 176 patients suffering from thyroid dysfunction and in 48 (9.1%) of 528 control subjects (OR = 0.66; 95% CI: 0.33–1.31; P = 0.23). Stratification by two groups of age (50 years and younger, and 51 year and older) showed that the youngest group of patients with thyroid dysfunction had a significantly lower seroprevalence of T. gondii infection than its age- and gender-matched control group (1/83: 1.2% vs 23/257: 8.6%; OR = 0.12; 95% CI: 0.01–0.93; P = 0.01). This stratification also showed that the youngest group of patients with hypothyroidism had a significantly lower seroprevalence of T. gondii infection than its age- and gender matched control group (0/75: 0% vs 21/233: 9.0%; P = 0.003).

Conclusions

Our results suggest that thyroid dysfunction is not associated with seropositivity to T. gondii in general; however, in young (50 years or less) patients, a negative association between infection and thyroid dysfunction and hypothyroidism was found. Further research to confirm this negative association is needed.

Knowledge and practices regarding toxoplasmosis in housewives: A cross sectional study in a northern Mexican city

We aimed to determine the knowledge and practices regarding toxoplasmosis among housewives in the northern Mexican city of Durango. One hundred eighty-five women (mean age: 41.27 ± 12.40 years old) with an occupation of housewife were studied. A self-administered questionnaire was used. This tool included items about the parasite Toxoplasma gondii, its transmission routes, general clinical, diagnostic, and treatment aspects of toxoplasmosis, and practices to avoid infection. A minority (<10%) of women knew about the parasite, the disease, how the transmission occurs, the clinical manifestations, how an infection is diagnosed, the treatment, and how to avoid toxoplasmosis. Some women knew that cats can transmit T. gondii infection (20%), and that the parasite can be found in cat feces (20.5%). Only 7.6% of women knew that infection with T. gondii can be transmitted by consumption of contaminated food or water. Only 1.1% of women knew about the prevalence of T. gondii infection. Some (4.9%) women used to taste raw meat while cooking, and 7.6% used to undercook meat. In addition, 20% of women used to eat raw dried meat, and 13.5% consumed untreated water. Less than 90% of women always washed their hands before cooking, and washed fruits or vegetables. The majority (75.1%) of women never wore gloves when handling raw meat. About one quarter (27.6%) of women always froze meat. And 16.2% of women cleaned cat feces. This is the first study regarding knowledge and practices about toxoplasmosis in housewives. Poor knowledge regarding T. gondii infection, toxoplasmosis, and practices to avoid infection among the housewives studied was found. High risk practices for infection were identified. Strategies to improve toxoplasmosis-related knowledge and practices to avoid T. gondii infection and its sequelae in housewives are highly needed.

Prevalence of Chlamydia trachomatis Infection Diagnosed by Polymerase Chain Reaction in Female Sex Workers in a Northern Mexican City

Purpose

We aimed to determine the association between Chlamydia trachomatis infection and female sex work, and the association between sociodemographic, obstetric, and behavioral characteristics of female sex workers and C. trachomatis infection.

Methods

Through a case–control study design, we studied 201 female sex workers and 201 age-matched women without sex work in Durango City, Mexico. C. trachomatis DNA was detected in cervical swab samples using polymerase chain reaction.

Results

C. trachomatis DNA was detected in 32 (15.9%) of the 201 cases and in 6 (3.0%) of the 201 controls (odds ratio [OR] = 6.15; 95% confidence interval [CI]: 2.5–15.0; P < 0.001). The frequency of infection with C. trachomatis in female sex workers did not vary (P > 0.05) regardless of the history of pregnancies, deliveries, cesarean sections, or miscarriages. Regression analysis of the behavioral characteristics showed that infection with C. trachomatis was associated only with consumption of alcohol (OR = 2.39; 95% CI: 1.0–5.71; P = 0.04). Conclusions: We conclude that C. trachomatis infection is associated with female sex work in Durango City, Mexico. This is the first age-matched case–control study on the prevalence of C. trachomatis infection in female sex workers in Mexico using detection of C. trachomatis DNA in cervical samples.

Human Papillomavirus Infection in Female Sex Workers: A Case Control Study

Background

To determine the association of infection with human papillomavirus (HPV) and the occupation of female sex worker; and the correlation of infection with HPV with sociodemographic, clinical and behavioral characteristics of female sex workers.

Methods

We performed a case-control study of 217 female sex workers and 354 women without sex work in Durango City, Mexico. We determined the prevalence of infection with HPV in cervical samples of women using polymerase chain reaction, and HPV genotypes were determined using line probe assay. Bivariate and multivariate analyses were used to assess the association between the characteristics of women and infection.

Results

Twelve (5.5%) of the 217 sex workers, and 10 (2.8%) of the 354 control women were positive for HPV DNA (age-adjusted OR = 1.51; 95% CI: 0.62 - 3.68; P = 0.36). Six (50.0%) of the 12 HPV DNA positive sex workers had infections with high-risk genotypes (16, 31, 33, 35, 51, 58). Seven (70%) of the 10 HPV DNA positive control women had infections with high-risk genotypes (16, 18, 56, 58, and 66). The frequency of high risk genotypes in the control women was equal with that found in the female sex workers (P = 0.41). Logistic regression analysis showed that the variable alcohol consumption was associated with HPV infection (OR = 4.0; 95% CI: 1.0 - 16.0; P = 0.04).

Conclusions

No association between HPV infection and female sex work was found in our setting. High risk HPV genotypes were prevalent among the women studied. Results can be used for the design of preventive measures against HPV infection.

A Case-Control Seroprevalence Study on the Association Between Toxoplasma gondii Infection and Bipolar Disorder

Background and Aims: Infection with the parasite Toxoplasma gondii has been associated with bipolar disorder in several countries other than Mexico. Therefore, we sought to determine the association between seropositivity to T. gondii and bipolar disorder in a Mexican population. Methods: We performed an age- and gender-matched case-control study of 66 patients with bipolar disorder (WHO International Classification of Diseases, 10th Revision code: F31) and 396 subjects without this disorder from the general population. Anti-Toxoplasma immunoglobulin G (IgG) and IgM antibodies were determined using commercially available enzyme-linked immunoassays. Results: Six (9.1%) of the 66 patients with bipolar disorder and 22 (5.6%) of the 396 controls had anti-T. gondii IgG antibodies (odds ratio [OR] = 1.7; 95% confidence interval [CI] = 0.66-4.36; P = 0.26). Stratification by gender and age did not show a difference in seroprevalence between cases and controls. The frequency of high (> 150 international units/ml) anti-T. gondii IgG levels was similar in cases (n = 2) and in controls (n = 12) (OR = 1.0; 95% CI = 0.21-4.57; P = 1.00). Stratification by International Classification of Diseases, 10th Revision F31 codes showed that patients with F31.3 code had a higher seroprevalence of T. gondii infection than their age- and gender-matched controls (OR = 16.4; 95% CI = 1.25-215.09; P = 0.04). None of the six anti-T. gondii IgG-seropositive patients with bipolar disorder and 4 (18.2%) of the 22 anti-T. gondii IgG-seropositive controls had anti-T. gondii IgM antibodies (P = 0.54). Conclusions: Our results suggest that T. gondii seropositivity is not associated with bipolar disorder in general. However, a specific type of bipolar disorder (F31.3) might be associated with T. gondii seropositivity. Further research to elucidate the role of T. gondii infection in bipolar disorder is needed.

Toxoplasma Gondii Infection and a History of Surgery: A Case Control Seroprevalence Study

We determined the association between having a history of surgery and the seroreactivity to T. gondii. An age- and gender-matched case-control study of 391 subjects with a history of surgery and 391 subjects without this history was performed. Sera of subjects were analyzed for detection of anti-T. gondii immunoglobulin G (IgG) and M (IgM) antibodies using enzyme-linked immunoassays. Anti-T. gondii IgG antibodies were found in 25 (6.4%) of the 391 cases and in 21 (5.4%) of the 391 controls (odds ratio [OR] = 1.29; 95% confidence interval [CI]: 0.66-2.18; P = 0.54). The frequency of cases with high IgG antibody levels (10/25: 40.0%) was equal to that found in controls (8/21: 38.1%) (OR = 1.08; 95% CI: 0.32-3.56; P = 0.89). Of the 25 anti-T. gondii IgG antibody seropositive cases, 5 (16.0%) were also positive for anti-T. gondii IgM antibodies. Meanwhile, of the 21 anti-T. gondii IgG antibody seropositive controls, 4 (19.0%) were also positive for anti-T gondii IgM antibodies (OR = 0.81; 95% CI: 0.17-3.72; P = 0.80). Logistic regression showed that only the variable "hysterectomy" was associated with T. gondii seropositivity (OR = 4.6; 95% CI: 1.6-13.4; P = 0.005). Results suggest that having a history of surgery is not an important risk factor for infection with T. gondii. However, the link between T. gondii infection and hysterectomy should be further investigated.

Association Between Suicidal Behavior and Clinical Features of Premenstrual Syndrome and Menstrual History: A Cross Sectional Study

BACKGROUND

The link between suicidal behavior and premenstrual syndrome has been poorly studied. This study aimed to determine the association of suicide attempts, and suicidal ideation and signs and symptoms of premenstrual syndrome and menstrual history in women in Durango City, Mexico.

METHODS

Using a cross-sectional study design, 437 women were interviewed to obtain clinical data about their premenstrual period, menstrual history and suicidal behavior. Logistic regression was used to assess the association between suicide behavior and clinical features of women. Odds ratio (OR) adjusted by age, presence of mental illness, and residence area, and 95% confidence interval (CI) were obtained.

RESULTS

Of these women, 29 (6.6%) had a history of suicidal ideation, and 15 (3.4%) had a history of suicide attempts. Logistic regression showed that suicidal ideation was associated with the variables: presence of irregular periods (OR = 2.89; 95% CI: 1.10 - 7.55; P = 0.03), low back pain (OR = 4.57; 95% CI: 1.31 - 15.92; P = 0.01), desire to eat certain food or eat a lot (OR = 2.47; 95% CI: 1.10 - 5.57; P = 0.02), guilty feeling (OR = 2.43; 95% CI: 1.06 - 5.59; P = 0.03), and aggressiveness (OR = 3.19; 95% CI: 1.42 - 7.13; P = 0.005). Whereas logistic regression showed that a history of suicide attempts was associated with the variables: presence of irregular periods (OR = 9.57; 95% CI: 1.23 - 74.44; P = 0.03), and desire to eat certain food or eat a lot (OR = 3.08; 95% CI: 1.04 - 9.15; P =0.04).

CONCLUSIONS

In this first study on the link of suicide behavior and clinical features of premenstrual syndrome, results suggest that suicidal ideation and suicide attempts are associated to specific signs or symptoms of premenstrual syndrome. Further research to confirm the findings of this study is needed. Results might help for an optimal planning of preventive measures against suicide.

Seroepidemiology of Leptospira Infection in Backyard Pigs in Durango State, Mexico

Purpose

This study aimed to determine the seroprevalence and correlates of Leptospira IgG antibodies in backyard pigs in the northern Mexican state of Durango. We performed a cross-sectional study of 305 backyard pigs. Anti-Leptospira IgG antibodies were detected using microscopic agglutination assay (MAT) with a panel of 12 Leptospira antigens.

Results

Overall, antibodies against Leptospira (any of the 12 Leptospira serovars examined) were found in 186 (61.0%) of the 305 pigs studied. Seropositive pigs were found on 80 (70.2%) of the 114 properties surveyed. The predominant serovar was Leptospira interrogans Pomona (n = 55); followed by Leptospira noguchii Lousiana and Leptospira santarosai Tarassovi (n = 53 each); L. interrogans Bataviae (n = 47); Leptospira biflexa Semaranga and L. interrogans Hebdomadis (n = 36 each); L. interrogans Pyrogenes (n = 30); L. interrogans Djasiman (n = 20); Leptospira borgpetersenii Ballum (n = 11); L. noguchii Panama and L. interrogans Canicola (n = 5 each); and L. borgpetersenii Mini (n = 2). Logistic regression showed that seropositivity was associated with low (<1000 m above sea level) altitude (odds ratio [OR] = 3.24; 95% confidence interval [CI]: 2.01–5.20; P < 0.001).

Conclusions

This is the first report of Leptospira exposure in backyard pigs in Mexico and of an association between Leptospira exposure in pigs and altitude. Backyard pigs represent a high-risk group for Leptospira exposure.

Apparently high Leptospira antibody seropositivity in donkeys for slaughter in three municipalities in Durango, Mexico

We determined the seropositive percentage and the determinants of Leptospira exposure in domestic donkeys presented for slaughter in the State of Durango, Mexico. We examined 194 donkeys in 4 gathering premises. Sera of donkeys were analyzed for anti- Leptospira IgG antibodies using a microscopic agglutination assay with a panel of 7 Leptospira antigens. The association between Leptospira seropositivity and general characteristics of donkeys was assessed by bivariate and multivariate analyses. Antibodies against Leptospira (for at least 1 of the 7 Leptospira serovars examined) were found in 151 of 194 (77.8%) donkeys. Seropositive donkeys were found in all regions, municipalities, and premises examined. The predominant serovar was L. interrogans Icterohaemorrhagiae ( n = 117; 60.3%), followed by L. interrogans Sejroe ( n = 96; 49.5%), L. interrogans Canicola ( n = 10; 5.2%), L. kirschneri Grippotyphosa ( n = 6; 3.1%), L. borgpetersenii Ballum ( n = 5; 2.6 %), L. biflexa Semaranga ( n = 3; 1.5%), and L. noguchii Panama ( n = 2; 1%). Leptospira seropositivity was associated with gathering premises (OR = 2.64; 95% CI: 1.27-5.46; p = 0.009) and municipalities (OR = 0.11; 95% CI: 0.01-0.78; p = 0.02). Our results demonstrate an apparently high seropositive percentage of Leptospira infection in the donkeys studied in Mexico.

Suicidal Ideation and Suicide Attempts in Middle-Aged Women Attending a Primary Care Center: A Cross-Sectional Study in Mexico

BACKGROUND

Very little is known about suicide attempts in middle-aged women in Mexico. The aims of this study were to determine: 1) the prevalence of suicidal ideation and suicide attempts in middle-aged women in Durango City, Mexico; and 2) the suicide attempt prevalence association with the sociodemographic, clinical, and behavioral characteristics of the women studied.

METHODS

Through a cross-sectional study, 395 middle-aged women were surveyed. Suicidal ideation, suicide attempt data, and the characteristics of the women were obtained with the aid of a questionnaire. Bivariate and multivariate analyses were used to determine the association between suicide attempts and the characteristics of women.

RESULTS

Of the 395 women (mean age: 46.97 ± 5.34 years) studied, 50 (12.7%) had suicide ideation, and 20 (5.1%) had suicide attempts. The number of suicide attempts among these 20 women varied from 1 to 10 times. The most frequent method used for suicide attempt was intake of medicaments (in 11 women). None of the sociodemographic characteristics was associated with suicide attempts. Women with suicide ideation, abdominal pain frequently, and reflexes impairment had a significantly higher frequency of suicide attempts than those without these characteristics. Logistic regression of behavioral variables showed that only the variable alcohol consumption was independently associated with suicide attempts (odds ratio = 2.82; 95% confidence interval: 1.01 - 7.84; P = 0.04).

CONCLUSIONS

Results suggest that suicidal ideation and suicide attempts are prevalent among women of middle-age attending a public primary care center in Durango City. This is the first report of an association between suicide attempts and reflexes impairment. Factors associated with suicide attempts found in this study may help in the design of preventive measures against suicide.

TNF-α Polymorphisms and Maternal Depression in a Mexican Mestizo Population

BACKGROUND

Depressive disorders are common during pregnancy. There is compelling evidence that the inflammatory response system is important in the pathophysiology of depression. Higher concentrations of proinflammatory cytokines including tumor necrosis factor-alpha (TNF-α) in depressed subjects have been described. Because several polymorphisms in the TNF-α promoter region are known to affect its gene expression, the aim of this study was determine whether TNF-α - 857C/T, -308G/A, and -238G/A polymorphisms confer susceptibility to depression during pregnancy in a Mexican mestizo population.

METHODS

This case-control study involved 153 depressed pregnant women and 177 controls. Polymorphisms were genotyped using real-time PCR. Odds ratios (OR) and 95% confidence intervals adjusted by age, body mass index, number of pregnancies, months of pregnancy and number of abortions were used to estimate risk.

RESULTS

The -857CT genotype was found to increase the risk for depression (OR= 1.73, 95% CI= 1.06-2.82). In contrast, the -238GA genotype reduced the risk (OR= 0.33, 95% CI= 0.14-0.72). The - 308G/A polymorphism was not associated with risk for depression. Finally, the C857-G308-A238 haplotype was associated with a decreased risk of depression (OR= 0.35, 95% CI= 0.15-0.82).

CONCLUSION

Our results show for the first time an association between TNF-α -857C/T and -238G/A polymorphisms and prenatal depression in Mexican mestizo population.

Toxoplasma gondii exposure and epilepsy: A matched case-control study in a public hospital in northern Mexico

Objectives

This study aimed to determine the association between infection with Toxoplasma gondii and epilepsy in patients attended to in a public hospital in the northern Mexican city of Durango.

Methods

We performed an age- and gender-matched case-control study of 99 patients suffering from epilepsy and 99 without epilepsy. Sera of participants were analyzed for anti-T. gondii IgG and IgM antibodies using commercially available enzyme-linked immunoassays. Seropositive samples to T. gondii were further analyzed for detection of T. gondii DNA by polymerase chain reaction.

Results

Anti-T. gondii IgG antibodies were found in 10 (10.1%) of the 99 cases and in 6 (6.1%) of the 99 controls (odds ratio = 1.74; 95% confidence interval: 0.60-4.99; p = 0.43). High (> 150 IU/mL) levels of anti-T. gondii IgG antibodies were found in 6 of the 99 cases and in 4 of the 99 controls (odds ratio = 1.53; 95% confidence interval: 0.41-5.60; p = 0.74). Anti-T. gondii IgM antibodies were found in 2 of the 10 IgG seropositive cases, and in 2 of the 6 IgG seropositive controls (odds ratio = 0.50; 95% confidence interval: 0.05-4.97; p = 0.60). T. gondii DNA was not found in any of the 10 anti-T. gondii IgG positive patients. Bivariate analysis of IgG seropositivity to T. gondii and International Statistical Classification of Diseases and related Health Problems, 10th Edition codes of epilepsy showed an association between seropositivity and G40.1 code (odds ratio = 22.0; 95% confidence interval: 2.59-186.5; p = 0.008). Logistic regression analysis showed an association between T. gondii infection and consumption of goat meat (odds ratio = 6.5; 95% confidence interval: 1.22-34.64; p = 0.02), unwashed raw vegetables (odds ratio = 26.3; 95% confidence interval: 2.61-265.23; p = 0.006), and tobacco use (odds ratio = 6.2; 95% confidence interval: 1.06-36.66; p = 0.04).

Conclusions

Results suggest that T. gondii infection does not increase the risk of epilepsy in our setting; however, infection might be linked to specific types of epilepsy. Factors associated with T. gondii infection found in this study may aid in the design of preventive measures against toxoplasmosis.

Association between Toxoplasma gondii infection and history of blood transfusion: a case-control seroprevalence study

Objectives

This study was performed to determine the association between seropositivity to Toxoplasma gondii and a history of blood transfusion.

Methods

Patients who had undergone blood transfusion (n = 410) and age- and sex-matched controls who had not undergone blood transfusion (n = 1230) were examined for anti-T. gondii IgG and IgM antibodies using enzyme-linked immunoassays.

Results

Anti-T. gondii IgG antibodies were detected in 57 (13.9%) patients and in 129 (10.5%) controls with a borderline difference [odds ratio (OR) = 1.37, 95% confidence interval (CI) = 0.98–1.92]. High anti-T. gondii IgG antibody levels (>150 IU/mL) were found in 27 (47.4%) of the 57 anti-T. gondii IgG-positive patients and in 37 (28.7%) of the 129 anti-T. gondii IgG positive controls with a significant difference (OR = 2.23, 95% CI = 1.17–4.26). Anti-T. gondii IgM antibodies were found in 13 (22.8%) of the 57 seropositive patients and in 37 (28.7%) of the 129 seropositive controls, but the difference was not significant (OR = 0.73, 95% CI = 0.35–1.52). Seroprevalence was significantly higher in patients aged >50 years than in controls of the same age and in female patients than in female controls.

Conclusions

These findings indicate that a history of blood transfusion is a risk factor for T. gondii infection.

Seroepidemiology of Cytomegalovirus Infection in Pregnant Women in the Central Mexican City of Aguascalientes

Background

Infection with cytomegalovirus (CMV) during pregnancy may lead to congenital disease. Very little is known about the seroepidemiology of CMV infection in pregnant women in Mexico. We sought to determine the seroprevalence and correlates of CMV infection in pregnant women in Aguascalientes City, Mexico.

Methods

Through a cross-sectional study design, 289 pregnant women were examined for anti-CMV IgG and IgM antibodies in Aguascalientes City, Mexico. A standardized questionnaire was used to obtain the socio-demographic, clinical and behavioral characteristics of the pregnant women. The association between CMV infection and the characteristics of the pregnant women was assessed by bivariate and multivariate analyses.

Results

Anti-CMV IgG antibodies were detected in 259 (89.6%) of the 289 pregnant women studied. None of the 289 pregnant women were positive for anti-CMV IgM antibodies. Seroprevalence of CMV infection was significantly lower (P = 0.03) in pregnant women with reflex impairment (5/8: 62.5%) than in those without this clinical feature (246/272: 90.4%). Seroprevalence of CMV infection was significantly higher (P = 0.03) in pregnant women with 2 - 9 pregnancies (140/150: 93.3%) than in those with only one pregnancy (119/139: 86.2%). Logistic regression analysis of socio-demographic and behavioral variables showed that seropositivity to CMV was associated with contact with children (odds ratio (OR) = 3.56; 95% confidence interval (CI): 1.17 - 10.84; P = 0.02), whereas high (> 150 AU/mL) anti-CMV antibody levels were negatively associated with washing hands before eating (OR = 0.17; 95% CI: 0.05 - 0.63; P = 0.007).

Conclusions

We found a high endemicity of CMV infection in pregnant women in Aguascalientes City, Mexico. Factors associated with CMV infection found in this study may be useful for an optimal planning of preventive measures against CMV exposure in pregnant women.

Seroepidemiology of Toxoplasma gondii Infection in Women of Reproductive Age: A Cross-Sectional Study in a Northwestern Mexican City

Background

Through a cross-sectional survey, we determined the seroprevalence and correlates of Toxoplasma gondii (T. gondii) infection in women of reproductive age in Hermosillo City, Mexico.

Methods

We studied 445 women of reproductive age in Hermosillo City in the northwestern Mexican state of Sonora. Women were enrolled in the University of Sonora. Sera of women were examined for IgG and IgM antibodies to T. gondii by commercially available enzyme immunoassays. The association of T. gondii seropositivity with the characteristics of the pregnant women was determined by bivariate and multivariate analyses.

Results

Of the 445 women (mean age: 22.18 ± 5.6 years) studied, 16 (3.6%) had IgG antibodies to T. gondii, and two (12.5%) were also positive for IgM antibodies to T. gondii. Of the 16 anti-T. gondii IgG-positive women, six (37.5%) had IgG levels higher than 150 IU/mL, four (25.0%) between 100 and 150 IU/mL, and six (37.5%) between 9 and 99 IU/mL. Multivariate analysis of socio-demographic and behavioral variables showed that T. gondii seropositivity was associated with older age (odds ratio (OR): 5.30; 95% confidence interval (CI): 1.37 - 20.50; P = 0.01) and boar meat consumption (OR: 6.86; 95% CI: 1.27 - 37.07; P = 0.02).

Conclusions

Women of reproductive age in Hermosillo City had a low seroprevalence of T. gondii infection. However, this finding indicates that most of these women were susceptible to a primary infection. Factors associated with T. gondii infection found in this study may be useful for the optimal planning of preventive measures against T. gondii infection and its sequelae.

Toxoplasma Gondii Exposure and Neurological Disorders: An Age- and Gender-Matched Case-Control Pilot Study

Little is known about the association of Toxoplasma gondii infection and neurological disorders. We performed a case-control study with 344 patients with neurological diseases and 344 neurologically healthy age- and gender-matched subjects. Sera of participants were analyzed for anti-T. gondii IgG and IgM antibodies using commercially available immunoassays. Anti-T. gondii IgG antibodies were detected in 25 (7.3%) cases and in 35 (10.2%) controls (odds ratio [OR] = 0.69; 95% confidence interval [CI]: 0.40-1.18; P = 0.17). Anti-T. gondii IgM antibodies were found in 5 (14.3%) of the 25 IgG seropositive cases and in 13 (37.1°%) of the 35 IgG seropositive controls (P = 0.15). Anti-T. gondii IgG antibodies were found in 8 (3.8%) of 213 female cases and in 23 (10.8%) of 213 female controls (OR = 0.32; 95% CI: 0.14-0.73; P = 0.005); and in 17 (13.0%) of 131 male cases and in 12 (9.2%) of 131 male controls (P = 0.32). No direct association between IgG seropositivity and specific neurological disorders was detected. We found no support for a role of latent T. gondii infection in the risk for neurological disorders in this setting. With respect to specific neurological disorders, further studies using larger patient cohorts will be required.

Toxoplasma gondii Infection and Headache: A Matched Case-Control Study in a Public Hospital in Durango City, Mexico

Background

Toxoplasma gondii (T. gondii) can disseminate to brain in infected hosts. Little is known about the magnitude of the association between this infection and headache. Therefore, we sought to determine the association of T. gondii seropositivity and headache in patients attending neurological consultations in a public hospital in Durango City, Mexico.

Methods

Through an age- and gender-matched case-control study, 105 patients suffering from headache and 105 subjects without headache were examined for anti-T. gondii IgG and IgM antibodies using commercially available enzyme-linked immunoassays. Seropositive cases were analyzed for detection of T. gondii DNA by polymerase chain reaction.

Results

Anti-T. gondii IgG antibodies were found in five (4.8%) of the 105 cases and in seven (6.7%) of the 105 controls (odds ratio (OR) = 0.70; 95% confidence interval (CI): 0.21 - 2.28; P = 0.76). The frequency of high (> 150 IU/mL) levels of anti-T. gondii IgG antibodies among anti-T. gondii IgG positive individuals was significantly (P = 0.01) higher in cases (5/5) than in controls (1/7). Anti-T. gondii IgM antibodies were found in one (20.0%) of the five IgG seropositive cases, and in three (42.9%) of the seven IgG seropositive controls (P = 0.60). T. gondii DNA was not detected in any of the five anti-T. gondii IgG positive cases. No association between T. gondii infection and specific headache types was found.

Conclusions

This is the first matched case-control study on the association between T. gondii infection and headache. Results suggest that high anti-T. gondii IgG antibody levels, but not T. gondii seropositivity, were associated with headache in the population studied.

Seroepidemiology of hepatitis E virus infection in pigs in Durango State, Mexico

No information about hepatitis E virus (HEV) infection in pigs in the northern Mexican state of Durango exists. We determined the seroprevalence and correlates of anti-HEV IgG antibodies in pigs in Durango, Mexico. Through a cross-sectional study, we studied 427 pigs raised in backyards (n = 328), or slaughtered (n = 99) in Durango. Sera of pigs were analyzed for anti-HEV IgG antibodies using a commercially available enzyme-linked immunoassay. Antibodies to HEV were found in 193 (45.2%) of the 427 pigs studied. A significantly higher seroprevalence was observed in slaughtered pigs (79.8%) than in backyard pigs (34.8%). Bivariate analysis showed that HEV seropositivity was associated with age, sex, breed, climate, altitude, mean annual temperature, mean annual rainfall, and farm raising. Logistic regression analysis showed that HEV seropositivity was associated with the origin (Sonora State) of pigs (OR=6.51; 95%CI: 3.74-11.32; P < 0.001), and mean annual rainfall (≤600 mm) (OR=1.78; 95%CI: 1.01-3.15; P = 0.04). A high seroprevalence of HEV infection in pigs slaughtered for human consumption in Durango City was found. This is the first report of an association between HEV seropositivity in pigs and climatic factors. Infection factors found may help for the optimal planning of preventive measures against HEV infection.

Seroepidemiology of Infection with Neospora Caninum, Leptospira, and Bovine Herpesvirus Type 1 in Water Buffaloes (Bubalus Bubalis) in Veracruz, Mexico

We aimed to determine the seroprevalence of infection with Neospora caninum, Leptospira, and bovine herpesvirus type 1 and risk factors associated with these infections in water buffaloes in Veracruz State, Mexico. Through a cross-sectional study, 144 water buffaloes (Bubalus bubalis) raised in 5 ranches of Veracruz were examined for anti-N. caninum and anti-bovine herpesvirus type 1 antibodies by enzyme immunoassays, and anti-Leptospira interrogans antibodies by microscopic agglutination test.

Of the 144 buffaloes studied, 35 (24.3%) were positive for N. caninum, 50 (34.7%) for Leptospira, and 83 (57.6%) for bovine herpes virus. The frequencies of leptospiral serovars in buffaloes were as follows: 18.7% for Muenchen (n = 27), 10.4% for Hardjo LT (n = 15), 9.0% for Pyrogenes (n = 13), and 4.8% for Icterohaemorrhagiae (n = 7). Seropositive buffaloes were found in all 5 ranches studied. Logistic regression showed that cohabitation of buffaloes with cows was associated with infection with Leptospira (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.04–4.5; P = 0.03) and bovine herpesvirus (OR, 12.0; 95% CI, 4.0–36.2; P < 0.01).

This is the first study that provides serological evidence of N. caninum, Leptospira, and bovine herpesvirus type 1 infections in water buffaloes in Mexico. Our findings could be used to enhance preventive measures against these infections.

Concordance of Toxoplasma gondii Infection Markers Among Heterosexual Couples

Background

Very little is known about concordance of Toxoplasma gondii (T. gondii) infection markers among couples. Through a cross-sectional study, we sought to determine the correlation of T. gondii infection in a sample of 119 heterosexual couples in Durango State, Mexico.

Methods

Participants were examined for the presence of anti-T. gondii IgG and IgM antibodies using enzyme-linked immunoassays. IgG and IgM seropositive couples were further analyzed for the presence of T. gondii DNA by using polymerase chain reaction (PCR).

Results

Anti-T. gondii IgG antibodies were found in 71 (59.7%) men and in 63 (52.9%) women (odds ratio (OR) = 1.31; 95% confidence interval (CI): 0.78 - 2.19; P = 0.29). Of the 71 seropositive men, 40 (56.3%) had a seropositive couple; in contrast, of the 63 seropositive women, 40 (63.5%) had a seropositive couple (OR = 0.74; 95% CI: 0.37 - 1.48; P = 0.39). In total, 65 (54.6%) couples had concordant results (both IgG positive or both IgG negative), and 54 (45.4%) had discordant results (a seropositive man with a seronegative woman, or a seropositive woman with a seronegative man) (kappa index = 0.08; 95% CI: -0.09 - 0.26). With respect to high (> 150 IU/mL) levels of anti-T. gondii IgG antibodies, 79 (66.4%) of the 119 couples had concordant results and 40 (33.6%) had discordant results (kappa index = -0.15; 95% CI: -0.03 - 0.33). Forty couples were positive for anti-T. gondii IgM antibodies. Of them, 21 (52.5%) had concordant results, and 19 (47.5%) had discordant results (kappa index = -0.01; 95% CI: -0.39 - 0.28). Concerning PCR, eight (50%) of 16 couples were positive for T. gondii DNA. Of them, 11 (68.8%) had concordant results, and five (31.2%) had discordant results (kappa index = 0.31; 95% CI: -0.17 - 0.79).

Conclusions

Results suggest a poor concordance of serological and molecular markers of T. gondii infection among heterosexual couples. Further studies to confirm our results should be conducted.

Seroepidemiology of Sarcocystis neurona and Neospora hughesi infections in domestic donkeys (Equus asinus) in Durango, Mexico

There is currently no information regarding Sarcocystis neurona and Neospora hughesi infections in donkeys in Mexico. Here, we determined the presence of antibodies against S. neurona and N. hughesi in donkeys in the northern Mexican state of Durango. Serum samples of 239 domestic donkeys (Equus asinus) were assayed for S. neurona and N. hughesi antibodies using home-made enzyme-linked immunoassays; six (2.5%) of the 239 donkeys tested seropositive for S. neurona. The seroprevalence of S. neurona infection was comparable among donkeys regardless of their origin, health status, or sex. Multivariate analysis showed that seropositivity to S. neurona was associated with increased age (OR = 2.95; 95% CI: 1.11–7.82; p = 0.02). Antibodies to N. hughesi were found in two (0.8%) of the 239 donkeys. Both exposed donkeys were healthy, 3- and 6-year-old females. This is the first evidence of S. neurona and N. hughesi infections in donkeys in Mexico.

Lack of Association Between Cytomegalovirus Infection and Hypertensive Disorders in Pregnancy: A Case-Control Study in Durango, Mexico

It is not clear whether infection with cytomegalovirus (CMV) is associated with hypertensive disorders in pregnant women. Through a case-control study design, 146 women suffering from hypertensive disorders in pregnancy (cases) and 146 age-matched normotensive pregnant women (controls) were examined for the presence of anti-CMV IgG and IgM antibodies with enzyme-linked immunoassays. IgM seropositive samples were further assayed by enzyme-linked fluorescent assay (ELFA).

Anti-CMV IgG antibodies were found in 138 (94.5%) controls and in 136 (93.2%) cases (odds ratio [OR] = 0.78; 95% confidence interval [CI]: 0.30–2.05; P = 0.62). High (>18 IU/ml) levels of anti-CMV IgG antibodies were found in 37.7% of the 138 seropositive controls and in 34.6% of the 136 seropositive cases (OR = 0.87; 95% CI: 0.53–1.43; P = 0.59). Anti-CMV IgM antibodies were found in 1 (0.7%) of the controls but in none of the cases using ELFA (P = 1.0). Seropositivity to CMV was not associated with a previous preeclampsia and was similar among cases regardless their mean systolic and diastolic blood pressures, and mean arterial blood pressure.

No serological evidence of an association between CMV infection and hypertensive disorders of pregnancy was found. Further research to elucidate the role of CMV in hypertensive disorders in pregnancy should be conducted.

Entamoeba histolytica Infection in Female Sex Workers: A Matched Case-Control Study in Durango, Mexico

Background

Infection with Entamoeba histolytica (E. histolytica) can be potentially transmitted by sexual contact. The seroepidemiology of E. histolytica in female sex workers has not been studied. The aim of the study was to determine whether E. histolytica is associated with the occupation of female sex work. In addition, the correlates of E. histolytica seroprevalence in female sex workers were also investigated.

Methods

We performed an age- and gender-matched case-control study of 187 female sex workers and 374 women without sex work. Cases and controls were tested for the presence of E. histolytica IgG antibodies using a commercially available enzyme-linked immunoassay. Seroprevalence association with the characteristics of female sex workers was determined by bivariate analysis.

Results

Anti-E. histolytica IgG antibodies were found in five (2.7%) of 187 female sex workers and in 16 (4.3%) of 374 controls (odds ratios (OR) = 0.61; 95% confidence intervals (CI): 0.22 - 1.70; P = 0.34). Mean optical density of the immunoassay in seropositive cases and controls was 1.35 ± 0.93 and 0.73 ± 0.45, respectively (P = 0.05). Seroprevalence of E. histolytica infection did not vary significantly with age, education, socioeconomic level, or health status of sex workers. Seropositivity to E. histolytica did not correlate with work characteristics such as duration in the occupation, condom use, type of sex, or a history of sexually transmitted diseases, or with behavioral variables such as washing hands before eating, or consumption of untreated water.

Conclusions

Results indicate that female sex workers do not have an increased risk for E. histolytica infection in Durango City, Mexico. Further studies to determine the risk of infection with E. histolytica by sexual contact should be conducted.

Lack of Serological and Molecular Association between Toxoplasma Gondii Exposure and Obesity: A Case-Control Study

The association between T. gondii infection and obesity has been scantly studied. Through an age-, and gender-matched case-control study, we determined the association of T. gondii infection and obesity using serological and molecular methods. Cases included 203 persons with obesity, and controls included 203 persons without obesity. Participants were tested for the presence of anti-Toxoplasma IgG antibodies using an enzyme-linked immunoassay (EIA). IgG seropositive individuals were further tested for the presence of anti-T. gondii IgM antibodies using an EIA, and T. gondii DNA by polymerase chain reaction (PCR). Anti-T. gondii IgG antibodies were found in 16 (7.9%) of the 203 cases and in 18 (8.9%) of the 203 controls (OR=0.87; 95% CI: 0.43-1.77; P=0.72). One (6.3%) of the 16 anti-T. gondii IgG seropositive cases and 6 (33.3%) of the 18 anti-T. gondii IgG seropositive controls were positive for IgM (P=0.09). Mean body mass index (35.5 ± 4.5) in T. gondii seropositive cases was similar (P=0.57) to that (36.1 ± 4.5) found in T. gondii seronegative cases. Stratification by obesity classes (I, II, and III) did not reveal differences (P>0.05) in seroprevalences (7.8%, 7.9%, and 8.1%, respectively) or high (>150 IU/ml) IgG antibody levels (3.3%, 3.9%, and 2.7%, respectively). PCR was positive in 5 (31.3%) of 16 cases, and in 5 (27.8%) of 18 controls examined (P=1.0). We found no serological or molecular evidence of an association between T. gondii infection and obesity in people attending a public health center in the northern Mexican city of Durango.

Lack of Association between Mannose-binding Lectin 2 Codons 54 and 57 Gene Polymorphisms and Cervicovaginal Infections in Mexican Women

The mannose-binding lectin (MBL) 2 gene has an important function in the innate immune response and activation of the third pathway of the complement system. Some studies have assessed the association of the MBL2 gene polymorphisms with cervicovaginal infections (CVI); however, there is no information about this association in Mexican women. This study aimed to determine the association between the MBL2 codons 54 and 57 gene polymorphisms with CVI in a sample of Mexican women. Through a cross-sectional study, blood samples and cervicovaginal cultures were obtain from 354 women. MBL2 genotyping was performed by real-time polymerase chain reaction with Taqman probes. Of the 354 women studied, 128 (36.2%) had CVI and 226 (63.8%) were healthy. The frequencies of the C and T variants in codon 54 in women with CVI were 83% and 17%, respectively; whereas the frequencies of these variants in healthy women were 82% and 18%, respectively. The frequencies of variants C/C, C/T, and T/T in women with CVI were 68%, 31%, and 1%, respectively; whereas the frequencies of these variants in healthy women were 68%, 29%, and 3%, respectively. With respect to codon 57, the frequencies of variants C and T were identical in women with CVI and in healthy women (97% and 3%, respectively). The frequencies of variants C/C, C/T, and T/T were identical in women with CVI and in healthy women (94%, 6%, and 0%, respectively). We conclude that MBL2 codons 54 and 57 gene polymorphisms do not associate with CVI in Mexican women.

Lack of Association Between Toxoplasma gondii Infection and Diabetes Mellitus: A Matched Case-Control Study in a Mexican Population

Background

Very little is known about the association between infection with Toxoplasma gondii (T. gondii) and diabetes mellitus. We perform an age- and gender-matched case-control study to determine the association of T. gondii infection and diabetes mellitus.

Methods

Cases included 156 patients with diabetes mellitus and 156 controls without diabetes mellitus who attended in two public clinics in Durango City, Mexico. Sera of cases and controls were tested for the presence of anti-Toxoplasma IgG and IgM antibodies using commercially available enzyme-linked fluorescence assays (ELFA).

Results

Anti-T. gondii IgG antibodies were found in 10 (6.4%) of the 156 cases and in five (3.2%) of the 156 controls (odds ratio (OR): 2.06; 95% confidence interval (CI): 0.69 - 6.19; P = 0.18). The frequency of high (> 150 IU/mL) anti-T. gondii IgG levels in seropositive cases (1/10: 10.0%) was comparable to the one (1/5: 20%) in seropositive controls (OR: 0.44; 95% CI: 0.02 - 9.03; P = 1.00). None of the 10 cases and five controls with seropositivity to anti-T. gondii IgG antibodies were positive for anti-T. gondii IgM antibodies. Stratification by gender showed similar frequencies of T. gondii infection in female cases (7/107: 6.5%) and female controls (4/107: 3.7%) (OR: 1.80; 95% CI: 0.51 - 6.34; P = 0.53), and in male cases (3/49: 6.1%) and male controls (1/49: 2.0%) (OR: 3.13; 95% CI: 0.31 - 31.19; P = 0.61).

Conclusions

We conclude that there is not serological evidence of an association between T. gondii infection and diabetes mellitus in the studied subjects in Durango City, Mexico. Further studies to elucidate the role of T. gondii in diabetes should be conducted.

Toxoplasma gondii exposure and Parkinson's disease: a case-control study

OBJECTIVES

To determine the association between Toxoplasma gondii infection and Parkinson's disease and to investigate whether T. gondii seropositivity is associated with the general characteristics of patients with Parkinson's disease.

DESIGN

Case-control study.

SETTING

Cases and controls were enrolled in Durango City, Mexico.

PARTICIPANTS

65 patients with Parkinson's disease and 195 age- and gender-matched control subjects without Parkinson's disease.

PRIMARY AND SECONDARY OUTCOME MEASURES

Serum samples of participants were analysed for anti-T. gondii IgG and IgM antibodies by commercially available enzyme-linked immunoassays. Prevalence of T. gondii DNA was determined in seropositive subjects using PCR. The association between clinical data and infection was examined by bivariate analysis.

RESULTS

Anti-T. gondii IgG antibodies were found in 6/65 cases (9.2%) and in 21/195 controls (10.8%) (OR 0.84; 95% CI 0.32 to 2.18; p=0.81). The frequency of high (>150 IU/mL) antibody levels was similar among cases and controls (p=0.34). None of the anti-T. gondii IgG positive cases and four of the anti-T. gondii IgG positive controls had anti-T. gondii IgM antibodies (p=0.54). The prevalence of T. gondii DNA was comparable in seropositive cases and controls (16.7% and 25%, respectively; p=1.0). Seroprevalence of T. gondii infection was associated with a young age onset of disease (p=0.03), high Unified Parkinson Disease Rating Scale scores (p=0.04) and depression (p=0.02). Seropositivity to T. gondii infection was lower in patients treated with pramipexole than in patients without this treatment (p=0.01). However, none of the associations remained significant after Bonferroni correction.

CONCLUSIONS

The results do not support an association between T. gondii infection and Parkinson's disease. However, T. gondii infection might have an influence on certain symptoms of Parkinson's disease. Further research to elucidate the role of T. gondii exposure on Parkinson's disease is warranted.

Influence of Toxoplasma Gondii Infection on Symptoms and Signs of Premenstrual Syndrome: A Cross-sectional Study

Infection with Toxoplasma gondii in brain may cause some symptoms that resemble those in women with premenstrual syndrome. To determine the association of T. gondii infection with symptoms and signs of premenstrual syndrome, we examined 489 women aged 30-40 years old. Sera of participants were analyzed for the presence of anti-Toxoplasma IgG and IgM antibodies using enzyme-linked immunoassays (EIA) and T. gondii DNA by polymerase chain reaction (PCR). Anti-T. gondii IgG antibodies were found in 38 (7.8%) of the women studied. Anti-T. gondii IgM antibodies were found in 13 (34.2%) of the 38 IgG seropositive women. Logistic regression showed two variables associated with seropositivity to T. gondii: presence of diarrhea (odds ratio [OR] = 6.10; 95% confidence interval [CI]: 1.37-27.85; P = 0.01) and weight gain (OR = 2.89; 95% CI: 1.37-6.07; P = 0.005), and two variables associated with high (>150 IU/ml) levels of IgG against T. gondii: presence of diarrhea (OR = 7.40; 95% CI: 1.79-30.46; P = 0.006) and abdominal inflammation (OR = 3.38; 95% CI: 1.13-10.10; P = 0.02). Positivity to EIA IgG and PCR was positively associated with obesity and negatively associated with joint pain by bivariate analysis. Our study for the first time reveals a potential association of T. gondii infection with clinical manifestations of premenstrual syndrome.

High Prevalence of Toxoplasma gondii Infection in Miners: A Case-Control Study in Rural Durango, Mexico

Background

Very little is known about the seroepidemiology of infection with the parasite Toxoplasma gondii (T. gondii) in miners. We determine the association of T. gondii infection and the occupation of miner, and the association of seropositivity for T. gondii with the socio-demographic, clinical, work and behavioral characteristics of the miners.

Methods

Through a case-control study, 125 miners working in Durango State, Mexico and 250 age- and gender-matched non-miner subjects were examined for the presence of anti-T. gondii IgG and IgM antibodies using enzyme-linked immunoassays. In addition, the presence of T. gondii DNA in miners was determined using polymerase chain reaction. Bivariate and multivariate analyses were used to determine the association of socio-demographic, work, clinical and behavioral characteristics of miners with T. gondii infection.

Results

Anti-T. gondii IgG antibodies were detected in 75 (60.0%) of 125 miners and in 55 (22.0%) of 250 controls (odds ratio (OR) = 5.31; 95% confidence interval (CI): 3.33 - 8.47; P < 0.001). Among IgG seropositive subjects, the frequency of anti-T. gondii IgM antibodies was significantly higher in miners (39/75, 52%) than in controls (8/55, 14.5%) (P < 0.001). All T. gondii seropositive miners referred themselves as healthy. Multivariate analysis of socio-demographic, housing, and behavioral characteristics of miners showed that T. gondii seropositivity was positively associated with being born in Durango State (OR = 3.44; 95% CI: 1.09 - 10.7; P = 0.03), consumption of boar meat (OR = 5.53; 95% CI: 1.49 - 20.3; P = 0.01), living in an overcrowded home (OR = 5.83; 95% CI: 1.49 - 22.8; P = 0.01), and was negatively associated with cleaning cat excrement (OR = 0.33; 95% CI: 0.11 - 0.90; P = 0.03) and consuming goat meat (OR = 0.16; 95% CI: 0.03 - 0.76; P = 0.02).

Conclusions

Surprisingly, our results indicate that miners represent a risk group for T. gondii infection. This is the first age- and gender-matched case-control study on the association of T. gondii infection and the occupation of miner. Further studies to identify the exact cause of high seropositivity in miners in rural Durango are needed.

SEROPREVALENCE AND RISK FACTORS ASSOCIATED WITH Toxoplasma gondii INFECTION AMONG RURAL COMMUNITIES IN NORTHERN IRAN

Toxoplasmosis is the fourth most common cause of hospitalization and the second cause of death due to food-borne infections. We conducted a cross-sectional study to determine the prevalence, disease awareness and risk factors associated with toxoplasmosis among rural communities in Northern Iran. Data were obtained from serological testing and from participant^'s questionnaires and were analyzed using a logistic regression. Of the 630 participants, 465 (73.8%), and 12 (1.9%) had IgG and both IgG and IgM anti-Toxoplasma gondii antibodies, respectively. In the logistic regression analysis, T. gondii seropositivity was associated with the following factors: age, occupation, consumption of undercooked meat, and of unwashed raw vegetables or fruits (p < 0.001). Our study showed a high prevalence of T. gondii infection in the general population of Northern Iran. A health program is needed to increase the public awareness of toxoplasmosis, and its associated risk factors.

Toxoplasma gondii Infection and Premenstrual Dysphoric Disorder: A Cross-Sectional Study

Background

Premenstrual dysphoric disorder is a severe form of premenstrual syndrome. The influence of Toxoplasma gondii (T. gondii) infection on clinical features in women with this disorder has not been studied. Therefore, we determined the association of T. gondii infection with symptoms and signs in women suffering from premenstrual dysphoric disorder.

Methods

We performed a cross-sectional study of 151 women suffering from premenstrual dysphoric disorder. Anti-Toxoplasma IgG and IgM antibodies were detected in sera of the participants using enzyme-linked immunoassays (EIAs). In addition, T. gondii DNA was detected in whole blood of IgG seropositive participants using polymerase chain reaction. We obtained the clinical data of women with the aid of a questionnaire. The association of T. gondii infection with clinical characteristics of women was assessed by bivariate and multivariate analyses.

Results

Anti-T. gondii IgG antibodies were found in 10 (6.6%) of the 151 women studied. Of the 10 IgG seropositive women, four (40.0%) were positive for anti-T. gondii IgM antibodies, and one (10.0%) for T. gondii DNA. Mean number (25.8 ± 7.58) of premenstrual clinical characteristics in seropositive women was similar to that (29.22 ± 9.13) found in seronegative women (P = 0.25). Logistic regression showed that seropositivity to T. gondii was negatively associated with difficulty concentrating (OR: 0.18; 95% CI: 0.03 - 0.91; P = 0.03), and positively associated with out of control feeling or overwhelmed (OR: 9.00; 95% CI: 1.32 - 62.00; P = 0.02).

Conclusions

Results of this first study on the association of T. gondii infection and clinical characteristics of premenstrual dysphoric disorder suggest that this infection might be linked to some symptoms of this disorder. We report for the first time the association of T. gondii infection and out of control feeling or overwhelmed. Results warrant for further research on the role of T. gondii in premenstrual dysphoric disorder.

Rubella Immune Status in Pregnant Women in a Northern Mexican City

BACKGROUND

The seroepidemiology of rubella virus infection in pregnant women in northern Mexico is largely unknown. We sought to determine the seroprevalence of rubella virus infection in pregnant women in the northern Mexican city of Durango, Mexico. Seroprevalence association with the socio-demographic, clinical and behavioral characteristics of the pregnant women was also investigated.

METHODS

Through a cross-sectional study, we determined the seroprevalence of IgG and IgM anti-rubella virus in 279 pregnant women (mean age 29.17 ± 5.96 years; range 15 - 43 years) attending in a clinic of family medicine using enzyme-linked fluorescent assays. A questionnaire was used to obtain the socio-demographic, clinical and behavioral characteristics of the pregnant women. The association of rubella seropositivity and characteristics of the women was assessed by bivariate and multivariate analyses.

RESULTS

Anti-rubella IgG antibodies (≥ 15 IU/mL) were found in 271 (97.1%) of the 279 pregnant women examined. None of the 279 pregnant women were positive for anti-rubella IgM antibodies. Multivariate analysis of socio-demographic, clinical and behavioral variables showed that seroreactivity to rubella virus was positively associated with national trips (OR = 7.39; 95% CI: 1.41 - 38.78; P = 0.01), and negatively associated with age (OR = 0.26; 95% CI: 0.06 - 0.99; P = 0.04).

CONCLUSIONS

Rate of rubella immunity in pregnant women in the northern Mexican city of Durango is high. However, nearly 3% of pregnant women are susceptible to rubella in our setting. Risk factors associated with rubella seropositivity found in this study may be useful for optimal design of preventive measures against rubella and its sequelae.